1              2                3 
Abc	bcb	dhd
	bce	dhdh
		Hdd

WHERE ((upper(a.idparent)=upper(:P24_SEARCH) or :P24_SEARCH='' or :P24_SEARCH=- 1 )
or (upper(a.idchild)=upper(:P24_SEARCH) or :P24_SEARCH='' or :P24_SEARCH=- 1 ))

Abc	bcb	
	bce

bce	       dhdh
	       Hdd

with x as (select  1  id, null par_id, '1 lvl' name from dual union all
           select  2  id,  1  par_id, '2 lvl' name from dual union all
           select  3  id,  1  par_id, '2 lvl' name from dual union all
           select  4  id,  3  par_id, '3 lvl' name from dual union all
           select  5  id,  3  par_id, '3 lvl' name from dual )

select id, par_id, name,sys_connect_by_path( name, ' -> ' ) scbp from x 
connect by prior id=par_id
start with id in (select id from x where x.id= 1 )